The Social Network

Sidebar: Keeping the Peace?

White-cheeked gibbons do not tolerate other gibbons in what they define as their territory. At the Zoo, the two gibbon pairs have visual contact with each other, but they are still kept apart. “You can keep gibbons in close proximity to each other successfully,” explains Lisa Stevens, curator of primates. “It’s about habituating them to their environment. However, they can be very aggressive to their neighbors, so you would never put them in the same enclosure.”

White-cheeked gibbon. (Mehgan Murphy/NZP)

If keepers observe any tension between animals in the same enclosure, they may place low-calorie snacks—such as browse or popcorn—throughout an enclosure as a distraction. To avoid any escalation, they refrain from putting out anything particularly savored by the primates.

Yet Zoo staff accept that a certain amount of aggression is inevitable. “Every social animal gets into a scuffle,” says Stevens. “Aggression and fighting are all part of the social lives of animals and primates. Whether its gorillas or gibbons, they have disputes that they need to resolve. We only intervene if there is injury.” It can at times even be socially detrimental to the animals for keepers to intervene in disagreements. “Often if you intervene, you delay the resolution of a conflict,” says Stevens.